sliced

The sliced crate is a thin wrapper around Vec that returns slices over internal storage rather than individual elements. It is useful in cases where you need to store and repeatedly manipulate a large collection of relatively short runs of numbers with the run lengths determined at run-time rather than during compilation. Using Vec<Vec<T>> means that each insert and remove will allocate and deallocate heap storage for the inner Vec, whereas sliced storage will use a single growable buffer.

For variable length slices, VarSlicedVec stores the sequences in a single Vec along with their extents using a compressed sparse layout.

use sliced::*;
let mut vv = VarSlicedVec::new();
vv.push(&[1, 2, 3]);
vv.push(&[4, 5]);
vv.push(&[6]);
assert_eq!(vv.remove(1), [4, 5]);
assert_eq!(vv.pop(), Some(vec![6]));
assert_eq!(vv[0], [1, 2, 3]);

For strings of equal length set at run-time, SlicedVec allows for constant-time insertion and removal without extra allocation if there is sufficient spare storage capacity.

use sliced::*;
let mut sv = SlicedVec::new(3);
sv.push(&[1, 2, 3]);
sv.push(&[4, 5, 6]);
sv.push(&[7, 8, 9]);
assert_eq!(sv.swap_remove(1), [4, 5, 6]);
assert_eq!(sv.pop(), Some(vec![7, 8, 9]));
assert_eq!(sv[0], [1, 2, 3]);

SlicedSlab is also provided for accessing segments using a key.

use sliced::*;
let mut ss = SlicedSlab::from_vec(3, (1..=9).collect());
assert_eq!(ss.get_keys(), vec![0, 1, 2]);
assert_eq!(ss[1], [4, 5, 6]);
ss.release(1);
assert_eq!(ss.insert(&[6, 5, 4]), 1);
assert_eq!(ss[1], [6, 5, 4]);

License: MIT